In April I changed my phone from pay-as-you-go to a monthly contract with T-Mobile. I did this through Phones4U, which notified T-Mobile to transfer my old number to my new phone. Somehow T-Mobile seems to have set up a second contract for a phone number I don't have. This may be from the sim card of the new phone which was replaced with my existing sim card. I only discovered its existence when I received a bank statement showing two direct debits. I've phoned and written to T-Mobile but no promised responses have ever materialised and I'm now being threatened with court action by a debt collection agency because I refuse to pay bills for a phone line number I've never had. DR, Shepperton, Middlesex

T-Mobile at first continued to insist that you were issued with two phones and that if the second (non-existent!) one was wrongly connected you must ask Phones4U to cancel the contract. Phones4U cannot do that since the contract exists only in T-Mobile's imagination. Give that T-Mobile has also changed your sex to female, its records are clearly not to be trusted. After six weeks of negotiation via its press office, it discovered it mistakenly set up a contract in your name using the sim card that you substituted. The fact that no calls were ever made on this number seems not to have occurred to anyone. It has now called off the bailiffs, cancelled the illusory contract and, as a goodwill gesture, reinstated you as a man.

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